ENUMERATED

This type alows you to model information which takes one of predefined values. There is not really an enumerated type (like BOOLEAN could be); instead, you can define your own one, such as:

DaysOfTheWeek ::= ENUMERATED {

sunday(0), monday(1), tuesday(2), wednesday(3), thursday(4), friday(5), saturday(6)

}

Priority ::= ENUMERATED {low(-1), medium(0), high(1)}

Although the notation is simmilar to notation of integers with distinguished values, there are some important differencies, besides the use of keyword ENUMERATED:

• the type defined is restricted to those values, that are named
• there is no numerical significance to the numbers involved; they are merely there to provide distinct representation for the various values
• there is no ordering relation defined
• only the identifiers, not the numbers, are used in the value notation

Thus it is purely correct to ommit those numbers in definitions. On the other hand, numbers are included, because of compatibility.